APPARATUS FOR RECORDING/REPRODUCING HOLOGRAHPIC DATA AND METHOD OF ADJUSTING POSITION OF RECORDING LAYER

摘要

PURPOSE: A holographic data recording/reproducing apparatus and a recording layer position adjusting method are provided to focus reference beam at the target depth by displacing a movable lens from a reference point corresponding to the target depth. CONSTITUTION: A holographic data recording/reproducing apparatus comprises a first and a second light source, an objective lens, a driving part, a focus shift part, a first and a second optical detector, and a controller. The objective lens reciprocates along an optical axis by the controller. The controller positions the focus of second beam in a desired recording layer by shifting the focus along the optical axial until the time difference between first and second detection signals reaches a value corresponding to the desired recording layer.